What are the two main steps of alcoholic fermentation?

The two main steps of alcoholic fermentation involve the conversion of pyruvic acid into ethanol and carbon dioxide, and choice B accurately describes this process.

First, pyruvic acid, which is generated during glycolysis, undergoes decarboxylation, where a carbon atom is removed in the form of carbon dioxide. This results in the formation of acetaldehyde. In the second step, acetaldehyde is then reduced by adding hydrogen atoms, which typically come from NADH, to produce ethanol. This process also regenerates NAD+, which is essential for glycolysis to continue, allowing for ATP production in the absence of oxygen.

This sequence is crucial for organisms that rely on fermentation in anaerobic conditions, enabling them to generate energy efficiently despite the lack of oxygen.